rogers



J.v HARRISA RoGRRs, or `nRwvoRK, N." Y.

l TELEPHONE.

sPEcIFIcATIoN forming part of Letters Patent No. 281,560, dated July 1v, 1883.

' `.ippncanonfile1`in1ar5f1e,wea (Remodel.)

f To aZwh/am traag/concern:

Beit known thatI, J AMns HARRrs ROGERS, a citizen of the United States, Yresidingin the city, county, and State of New York, 'have invented'certain new and useful Improvements in rlelephones, of which Jthe following is a specification.

My invention relates to that form of ,telephonic transmitters in which the diaphragm receiving the sound-vibrations iniiuenc'es the perfectness of contact of the circuit-terminals;

and its object is to furnish a transmitter sim- `ple in construction, effective in operation, and

without necessity of delicate adjustment.

To these ends the invention may beV stated generally as consisting of a transmitter sov constructed that'the normal contact of the circuit terminals or electrodes therein is due simply to gravity. To accomplish this the diaphragm used, which may be of any desired material, is mounted in a frame, by which it may be supported in a horizontal position. A suitable frame for this purpose is readily formed of two plates of insulating material thickened at the edges b'y'a rim or abutment, so that when joined together at such edges a chamber for the diaphragm is formed between them, across which extends said diaphragm, it being secured at its edges between the plates.A Attached to the lower plate, and opening into chamber beneath the diaphragm, is curved a mouth-piece, preferably of trumpetshape, for condensing and converging to the diaphragm `the sound-vibrations to be reproduced. Upon the diaphragm, in the simplest form of the transmitter, lies a carbon plateor button, resting and held thereon simply by its own weight. In practice, when the diaphragm is a conductor, and it is so desired, it forms one electrode, while the carbon plate or button forms the other. By such an arrangement asimple and effective transmitter is formed in which no delicate adjustments are required. Starting with this simple principle of construction, the mechanical details may be varied in .several ways, some of which are hereinafter referred to.

In the accompanying drawings, Figure 1 represents a side elevation of my improved telephone. Fig. 2 represents a sectional view of a transmitter complete. Figs. 3 and 4 are 1in the top diagrammatic views showing various modica-l tions ofthe above. Inthese latter viewsthe` case is omitted and simply the operative portions conventionally represented. s

In Figs. l and 2, E E are the sides of the inclosing-case. These sides are formed each with a fringe or projecting rimk or ilange, e e',

.the..two,' when placed together, forming .the chamber O between them.v In this chamber, secured at its edges between the rim e e', is placed the diaphragm D. For this diaphragm carbon seems very suitable, giving in use eX- jcellent4 results 5 but any other material capable of vibration may be used. Entering into and supported from the bottom plate, E, of the case is the curved mouthl` piece T, made preferably7 as-shown, of trumplet shape. Upon the top of the diaphragm rests 'loosely the flat carbon plate or button 0,1 I

as shown in Fig. 2. A small cavity is formed d-rop of mercury.

thereof, in which may be placed a f Attached to the upper plate, E, of the case is a dome or support, F, through which passes a' screw, S,'in the lower end of which is xed a needlen, dipping into the dropv of mercury inthe'v cavity of the plate or button C.v By

means offthe screwSthe amount vof contact of t the needle and mercury may be regulated and, if necessary, the force of contact between the diaphragm and plate or button be augmented. At B is shown in diagram the battery, and at G the customary ground-connection.

The relative arrangement here shown of the mouth-piece T and dome or support F may be varied without departing from the spirit of my invention.

The diaphragm D may be formed of carbon -or any other suitable conductor, and to the said diaphragm is connected one terminal, the other terminal being connected to the screw S, so that the circuit is established through the diaphragm, the plate or button resting thereon, the mercury therein, and the needle or screw forming thereby an exceedingly sensitive though simple means of varying the tension of the line.

In Fig. 3 two buttons or plates, C C', are laid, one above the other,

on the diaphragm,

the upper button being provided with mercury 10o or other suitable material, in which dips the end of a needle in the end of screw, S', as explained in connection with Fie. 2. In Fig. 4 two or more independent plates or buttons, C C, are laid upon the diaphragm, and adjustingscrews S S are provided for each button, their mercury-contact and adjusting-screws being arranged as in the ease of the form shown in Fig. 2.

The methods of construction herein shown avoid the use of delicate springs for holding the carbon buttons, obviate the necessity of frequent adjustments, lessen the risk of failure in the instrument, and furnish a simple and effective instrument throughout.

It will be seen that in making the contactplates fiat I am enabled to increase their number by placing them one above the other, the top one always being connected to the linewire and forming one pole of the circuit. In this duplication the plates rest, as before cX- plained, by their own weight, one upon the other. By this means, also, they are adapted to retain the mercurya thing impossible in a round button or any button and supporting` diaphragm whose contact portions do not remain in a constant relation.

It is to be understood that no stress is to be laid upon the material of the diaphragm, a though carbon is excellent therefor, but the principle involved is equally applicable to any kind of diaphragm. It is to be understood, also, that wherever the instruments are shown or described as connected to the line it is not essential that they be so connected, for they may be connected in the primary circuit of an induction-coil of which the secondary is connected to the line, as usual. The batteries,

ground and line connections may also be varied, and such constructions madeas desired..

I wish it to be distinctly uiulcrstoodthat all matter of my invention herein shown and de scribed but not specifically claimed I reserve yfor future application.

Having thus described my inve11tio11,-, the 45 following is what I claim as new therein and desire to secureby Letters Patent:

1. In combination with the horizontal diaphragm of a telephone-transmitter connected to a battery and forming one pole of an electric-circuit, as described, the flattened plate or button lying loosely and simply by its own weight upon the diaphragm, and connected to a line-wire and forming the opposite pole of said circuit, as set forth.

2. In a telepho11e-transmitter, the combination of ahorizontal diaphragm, forming one v pole of an electric circuit, with a flattened plate or button, forming the opposite pole, and resting on the diaphragm and adapted to receive soundwibrations therefrom, as described, the said plate having a quantity of mercury in its upper part, and a connection with a line-wire consisting of a dipping-needle, substantially as set forth.

3. In a telephone-transmitter, the combination of the horizontal diaphragm, rthe inclosingcase, trumpet mouth-piece, .the ilattened contact plate or button resting on the sensitive diaphragm, as described, the said plate or button being provided with a cavity in its top adapted to receive mereury,'and the superimposed dome provided with a dipping-needle and a regulating-screw, all substantially as and for the purposes set forth.

4. In combination with the horizontal diaphragm, forming one pole of an electric circuit, and the contact-plate or button provided with mercury in its uppei'portion, as described, the

superimposed dome F, h: ving a screw, S, connected to a line-wire, and having a needle, n, as and for the purposes set forth.

J. II. ROGERS.

\Vitnesses:

H. J. lNNis, J. XV. Romans. 

